Driving sustainability excellence on Tonkin Gap
At a glance
As part of the Tonkin Gap Alliance, we led the development and implementation of a comprehensive sustainability management system that was effectively integrated on the Tonkin Gap Project and Associated Works. Our efforts supported the project in embedding sustainability into the design and construction processes, contributing to its success in achieving a Gold v2.0 Infrastructure Sustainability (IS) rating.
The Tonkin Gap Project and Associated Works was delivered by BMD, Georgiou, WA Limestone, GHD and BG&E, together with Main Roads and the Public Transport Authority.
The challenge
Since the introduction of the v2.0 IS Planning tool in 2018, Main Roads has committed to achieving IS Planning ratings on all projects over $100M, meaning that sustainability would need to be embedded early in the process to set the project up for delivery. However, the Tonkin Gap Project and Associated Works was fast tracked as part of Western Australia’s economic recovery efforts following the impacts of COVID-19, resulting in a reduced scope of preliminary development work and, notably, the absence of sustainability planning work.
The project team was committed to treating sustainability not as an afterthought in major infrastructure development and construction, but as an integral element throughout the project lifecycle. The project had a target to achieve a Silver IS rating, with several contractual commitments aimed at reducing material, water and energy footprints, along with meeting other minimum credit requirements.
Without having an existing sustainability framework, it was crucial for our team to quickly identify key sustainability focus areas to guide project delivery. We recognised the importance of developing cohesive systems and processes to support the seamless integration of sustainability into the design, procurement and construction phases.
Our response
At the outset of the Alliance formation, sustainability was embedded into the governance structure with an Environment and Sustainability Manager being part of the Alliance Management team. This integration positioned sustainability as a key consideration in broader project decision-making, influencing outcomes throughout the project lifecycle. Risks and opportunities related to sustainability could be raised directly with the senior management team, making it a core agenda item throughout both the design and construction phases.
We were able to influence the procurement approach, working closely with the commercial team to develop a multi-criteria procurement analysis. This included priority sustainability criteria across social, environmental and economic themes, alongside financial criteria for the evaluation of all vendors engaged in the project. This followed an early sustainable procurement workshop, facilitated by GHD, to identify sustainability risks and opportunities within the supply chain, which influenced how the Alliance engaged with subcontractors.
A sustainability framework, outlining focus areas, objectives and targets, informed sustainability risk and opportunity processes, allowing us to concentrate our efforts on implementing initiatives with the greatest impact on the project and the client, particularly in relation to priority sustainability topics. This also involved developing a bespoke decision-making tool, incorporating a range of sustainability criteria and lifecycle cost analysis, which was extensively adopted in the assessment of design and value engineering initiatives.
Over time, we identified an opportunity to further influence sustainability outcomes during construction by providing targeted training and resources. We launched the ‘Sustainability Essentials’ initiative, introducing six key sustainability principles for construction. This initiative promoted priority considerations for each topic, helping the team better understand the broad impact and the role they played in influencing sustainable outcomes.
The impact
Our collaborative and integrated approach to sustainability led to significant outcomes across social, environmental and economic aspects, while exceeding expectations for both our contractual requirements and the IS rating, achieving Gold – a step beyond the initial target of Silver. We cultivated a strong sustainability culture within the Alliance Management team, which successfully cascaded to all members contributing to these achievements.
The new processes that we established supported innovation in complex technical solutions and the exploration of sustainable materials, further aligning with our vision of driving circular economy outcomes. By influencing design and construction methodologies, we achieved lifecycle reductions of 14% in water usage, 19% in embodied carbon, and 9% in energy consumption.
Our efforts to upskill the wider team in sustainability were key to maintaining a continuous improvement mindset and creating a sense of shared responsibility for achieving sustainable outcomes. This approach set a new benchmark for sustainable infrastructure development in Western Australia, with the project becoming the first in the state to receive the Gold Sustainability ranking from the ISC, despite being fast-tracked as part of the state's economic recovery efforts following the impacts of COVID-19.